190 



THE MUSCLES. 



the atlas (Fig. 105, 9). c, d. The two or three others are directly inserted 

 into the transverse processes of the third, fourth, and fifth cervical 

 vertebras. 



Relatiom. — The splenius is related, outwardly, to the rhomboideus, the 

 angularis, cervical trapezius, and mastoido-humeralis ; inwardly, to the two 

 complexus and two oblique muscles of the head ; by its inferior border, to 

 the superior margin of the inferior branch of the ilio-spinalis (longissimus 

 dorsi). 



Action. — It extends the head and neck in incliniag them to one side. If 

 the two act in concert, the extension is direct. 



Fig. 102. 



StrPBRFIOIAL MUSCLES OF THE NECK AND SPINAL REGION OF THE BACK AND LOINS. 

 1, Dorsal trapezius ; 2, Great dorsal ; 3, Cervical trapezius ; 4, Leyator angull 

 scapula; ; 5, Splenius ; 6, Anterior, or superficial portion of the mastoido-hume- 

 ralis ; 7, Its humeral insertion ; 7' Its mastoid insertion ; 8, The thin aponeurosis 

 uniting this insertion to the sterno-maxillary. muscle; 8', Posterior portion of the 

 mastoido-humeralis ; 9, Its inferior aponeurosis inserted into the interstice of the 

 long abductor of the arm ; 10, Ster^-maxillaris ; 11, Subscapijlo-hyoideus; 12, 

 Portion of the dermal muscle of the jiSck ; 13, Portion of the' great extensor of 

 the fore-arm ; 14, Posterior belly of the long abductor of the arm : 15, Great 

 pectoral muscle. 



